1. Field of the Invention
The present invention relates to an exposure controlling blade for use in silver-chloride-type cameras and magnetic recording cameras and adapted for controlling apertures or shutters in such cameras. More particularly, the present invention is concerned with the construction of pins which are fixed to each blade of the exposure controlling blade device for the purpose of controlling the rotational movement of the blade. Still more particularly, the invention is concerned with an art for fixing such pins to the blade for the exposure controlling.
2. Related Background Art
In a typical conventional technique for fixing pins to each blade of an exposure controlling blade, the pins are fixed by caulking to the blade which is made of a suitable material such as an SK steel, duralumin or a polyester resin. It has also been a known practice to fix pins made from a plastic material by melting and welding the same to each blade of the exposure controlling blade device. Such fixing methods are disclosed, for example, in Japanese Utility Model Laid-Open No. 134023/1981.
These known fixing methods, however, are disadvantageous in that the blades in the exposure controlling blade device which make sliding contact with one another at their surfaces tend to be damaged by protrusions which are inevitably formed on each blade as a result of the caulking or fusion welding when the pins are fixed to each blade. The protrusion on each blade also impairs the flatness or smoothness of the plane of the surfaces of each blade, resulting in troubles such as, for example, deterioration in the precision of aperture diameter particularly when the aperture diameter is small.